High temperature composite propellant system



United States Patent Ice 3,463,682

Patented Aug. 26, 1969 3463682 Percentb wei ht HIGH TEMPERATURE COMPOSITE y g PROPELLANT SYSTEM Component (1) (2) (3) Joseph T. Hamrick, 6364 Jae Valley Road SE.,

. 0 9 Roanoke County, Va. 24014 D 3:; 1 No Drawing. Filed Feb. 13, 1967, Ser. No. 615,345 5 11.00 11-00 11-00 Int C C06) 1/00 1/00 Magnesium (lIlSll 13.04 13. 47 14. 30 Cyanuric acid 26.45 25.95 24. 98 U8. Cl. 149-19 1 C a Barium nitrate as 51 38.58 38.72 Heat of reaction, B.t.u./lb. 946 960 987 Computed chamber temp, F 3, 400 3, 600 3, 800

ABSTRACT OF THE DISCLOSURE The invention consists of a composite solid propellant which will withstand 600 F. for at least two hours, 500 F. for more than 48 hours, and 450 F. for over 400 hours without significant change in performance.

Pressure generated in a vented vessel are as follows:

Specimen Specimen Firing Vent Pressure len h, a., temp. dia., generated, Test No. inches inches Wt., gins. F.) inches p.s.i.g.

The present invention relates broadly to the formulation A 33.5 gm. specimen was held at 5 00 F. for 24 hours of propellant mixtures which are suitable for use in high Wlth a gram Weight 1085- The Same Specimen a temperature 6nvirnment8 at 500 F. for an additional 24 hours with an additional .6 gram weight loss. A specimen was held at 600 F. for It IS the pnnclpaIl mm of thls.mver.ltmn to provide a two hours without signs of physical deterioration. The propellant formulation system which Wlll allow prolonged weight loss was not recorded. exposure of devices 1n which it 1s used to temperatures propellants were made and tested in which barium in the 500 F. to 600 F. range. perchlorate was substituted for barium nitrate. However,

It is a further objective to provide a solid pyrotechnic barium perchlorate made the propellant more hygroscopic Substance hi h h i i d at any temperature f om than barium nitrate and is considered less desirable from R or lower to approximately F. will Provide that standpomt although satisfactory otherwise. .Addihigh pressure gases for the purpose of actuating devices tional Teflon can also be substituted for the barium nitrate. which require high Pressure gases or liquids in order However, propellant samples for which this was done had less desirable physical properties. to function. Other ob ects and advantages of the present propellants were also made and tested using oxamide in n will become more apparent during the course (C H 'N O as a substitute for cyanuric acid. These proof the following description. pellants were satisfactory for prolonged storage at 400 Applicants invention lies principally in the discovery but were margillfllly acceptable at F due to that chemicals which are virtually inert up to their hmation of the oxamide on the propellant surface at composition temperatures can be mixed and bound solidly that mperature to ether with a hi h tem erature resistant fuel and oxi- I clam i my mventmi g p 1. A sohd propellant WhlCh will withstand temperatures dizer, the resulting solid when ignited m a vented vessel in the 400 to 600 F. range and consisting essentially of dec p g the Inert chemlcal thereby generatmg gases 5 to 30 weight percent of a fuel, magnesium dust; 5 to at high pressure and at temperatures which vary with 30 weight percent of oxidizer, polytetrafluoroethylene; 5 the percentages of ingredients. Results from one combinato 30 weight percent of oxidizer, copolymer of hexafluorotion of ingredients are shown in the following example. Propylene and Vinylidene fluoride; 30 to 50 Weight P cent of an oxidizer selected from the group consisting of barium nitrate and barium perchlorate; approximately .05 weight percent of cross linking agent, hexamethylenc- The principal ingredients of one mixture that has underdiamine; and 10 to 40 percent of a coolant selected from gone testing are cyanuric acid (C H N O magnesium the group consisting of cyanuric acid epowder, Teflon (polytetrafluoroethylene), Viton (Copolymer of hexafluoropropylene and vinylidene fluoride), and

Example References Cited barium nitrate. The Teflon and Viton, which are supplied UNITED STATES PATENTS by E. I. du Pont de Nemours & Company and barium 1,756,255 4/ 1930 Meek 144 .43 X nitrate are the oxidizing ingredients. They react with the .9 3 6 Wiley 149-43 magnesium powder upon ignition. A fifth ingredient, Diak 1 gi ii et a1 "1-4 (hexamethylenediamme carbamate), which is also a prod- 3:122:462 2/1964 Kaufman 149 22 X net of E. I. du Pont de Nemours & Company, serves to 3,163,113 12/1964 Davis et a1 X chemically cross link the molecules of Viton. The Viton- 3,203,171 8/1965 Burke et a1 149 44 X Teflon binder provides good physical characteristics over the entire temperature range from -'65 F. to 600 F. 70 BENJAMIN PADGETT Primary Exammer The following compositions have been tested with excels CL lent results: 149--20, 42, 43, 44 

